DFU mode restore
Only on T2 Macs!
- 2018+ A1989/A2159 13" MacBook Pro
- 2018+ A1990 15" MacBook Pro
- 2018+ A1932 13" MacBook Air
- 2018+ A1993 Mac mini
- 2017 A1862 iMac Pro
- 2019 A1991 Mac Pro
DFU mode is needed (rarely) to restore the T2 firmware when:
- Failed macOS upgrade/reinstall/Security Update
- Failed Combo or Delta update
- Unable to boot into the current OS Internet Recovery using command + option + R
DO NOT DFU IF TARGET MAC IS ON BETA SOFTWARE. THIS WILL BRICK THE MAC AND YOU WILL HAVE TO DO THE WALK OF SHAME TO AN APPLE STORE.
THIS WILL NOT WORK IF FIRMWARE PROTECTION IS ON.
You will need:
- a host Mac which has USB-C, minimum OS of 10.13.5, Apple Configurator 2.6 or newer installed (from App Store), and an internet connection.
- USB-C cable which supports data and power or Thunderbolt 3 cable.
- Target Mac (one that is being put in DFU) is connected to power. Do not use the left port closest to track pad for power - you will need this for data.
Make sure Host Mac is powered up, iTunes is not open if applicable (fully quit) and open Apple Configurator 2.
For MacBook Pro and MacBook Air - Make sure Mac is shut down (hold power button for 5 seconds). Plug in data cable to Host Mac (any port) then into the left port closest to track pad in the Target Mac. Hold right shift + left option + left control + power keys simultaneously for about 3 seconds (according to Apple, other sources say 4-8 seconds). NOTE: We found that if you press the power button for 1 one thousand and then simultaneously hold the right shift + left option + left control, you should be successful each time. We also found that we were able to get in DFU mode around 4 to 6 (one one thousand, etc.) seconds. The Target Mac will remain as a black screen but you should see the DFU box pop up in Apple Configurator window on the Host Mac.
For Mac mini and iMac Pro - Disconnect power cord from Target Mac. Plug in data cable on Target Mac to port closest to ethernet. Hold down power button and plug the power cord back in. Continue holding power button for about 3 seconds. The Target Mac will remain as a black screen but you should see the DFU logo in Apple Configurator window.
It is assumed the 2019 Mac Pro instructions will be similar to Mac mini and iMac Pro but cannot be confirmed until they are officially released.
Complete the restore through Apple Configurator. When done, verify that the process completed.
Few things from experience (inwerp):
Case: Macbook Pro 2018 15', 5V shortly 0.3A, than 0.04A-0.08 floating, all G3HOT present. Died with no particular reason, stopped charging and simply did not start up after next reboot.
- Did not work with USBA-USBC adapter (claimed to work by Apple Article), used thunderbolt cable.
- Apple Configurator shows DFU logo without key combination, but flashing in this mode will end up with a undefined error.
- Key combination works like 50/50, no particular pattern, best looks like DFU LOGO - SMC RESET Combo 4 Sec till DFU Logo disappears, shows again, now flashing works.
may end up with the connection timeout, target device will start to boot, then shutdown at some point.
Macbook Air 2018 (820-01521) no power no post, just died, stuck at 20V 0.0667A All G3H present, missing PP5V_S5.
Connected power to the USB that is close to the LCD, and the USB c to the host machine close to the Tarckpad.
Using a host MacBook air with configurator 2, manage to prompt recovery. Clicked the restore button the the process started.
The restore process stalled at the last few pixels of the progress bar, and the Target Air turned off.
Upon pressing the power button, the Target air went in to internet recovery, from where the installer prompted "Activating Mac", which got Activated.
Disk utility showed an empty disk.
In this case Data was wiped from customer's device.